Method of treating waters



Reissued Jan. 13, 1953 METHOD OF TREATING WATERS, INCLUD- ING BOILERWATERS, AND COMPOSITION THEREFOR Wayne L. Denman, Oak Park, 111.,assignor to Dear-born Chemical Company, Chicago, 111., a corporation ofIllinois No Drawing.

Original No. 2,400,543, dated May 21, 1948, Serial No. 321,140, February27, 1940. Application for reissue March 1, 1952, Serial No.

29 Claims.

The present invention relates to the treatment of waters, or aqueousbaths, having present ingredients inducing foaming. More particularly,waters'of the above character are treated with amines or more especiallyaliphatic amines. which are sparingly soluble, or substantiallyinsoluble in the water being treated, preferably do not steam distill toany substantial extent, and exhibit little tendency to saponify with theingredients of the water or aqueous bath.

The invention, in its narrower form, contemplates the treatment ofwaters with saturated and/or unsaturated aliphatic amines. saidcompounds containing eleven (11) or more carbon atoms, beingsubstantially insoluble in water, and showing little tendency to steamdistill. In the more specific form of the invention, said compounds areused to inhibit the foaming tendency of raw or softened alkaline watersand particularly boiler waters having excess alkalinity, or analkalinity present in a quantity more than suilicient to combine withthe calcium and/or magnesium ions, salts or their equivalents containedin the water.

It may be stated that the solubility of the aliphatic amines in waterdecreases with the molecular weight thereof, and, therefore, inaccordance with the present invention, it is preferred to use thoseamine compounds which have a high molecular weight, and by this is meantcompounds having eleven (11) carbon atoms or more, and typified byundecyl amine, dodecyl amine, tridecyl amine, and the like, these allbeing straight chain primary amines.

As previously pointed out, aliphatic amines which are sparingly soluble,or substantially insoluble, may be used as the primary anti-foam agentin a composition adapted to inhibit the foaming in waters containingingredients inducing foaming therein. These amines are particularlycapable of giving satisfactory results in j inhibiting the foamingtendency of waters con- 'taining excess alkalinity, and particularlyexcess sodium and potassium alkalinity. These amines as a'group showsubstantially no tendency" to saponify in the water or aqueous bathtreated. Preferably, where the water treated is subjected to a hightemperature, the aliphatic amines should not steam distill to anymaterial extent. Examples-of aliphatic amines which may be used inaccordance with the present invention are hexadecyl amine (CuHssNHs),heptadecyl amine Matter enclosed in heavy brackets I: II appears in theoriginal patent but forms no part of this reissue specification; matterprinted in italics Indicates the additions made by reissue.

2 (CnHasNHs), octadecyl amine (CISHTTNI'IJ), and secondary octyl amine(CaHnNI-ICaHu).

It may be pointed out that in accordance with the present invention, itis the intention to use the broad class of amines, either aliphatic oraromatic, which are sparingly soluble, or substslntially insoluble inwater, and which prevent the foaming of the water or the aqueous bathtreated. Generally, it is the amines of high molecular weight which arethe most satisfactory, and as a general rule, it may be stated that themost insoluble ones are the amines which contain more than ten (10)carbon atoms. particularly the straight chain primary amines. However,it may be pointed out that the split chain primary amines, as well asthe straight chain and split chain secondary and tertiary amines, may beused in accordance with the present invention.

Other straight chain primary amines which may be used as an anti-foamagent are:

Undecyl amine (CuHnNHz) Dodecyl amine (CmHzsNI-Iz) Tridecyl amine(CnHz'INI-h) Tetradecyl amine (cammmi Pentadecyl amine (CulbiNHi)Nonadecyl amine (CnHsnNHa) Eicosyl amine (CaoHuNI-Is) Heneicosyl amine(CmHnNI-Is) Docosyl amine (Cazl-hsNHz) Tricosyl amine (CmHflNHs)Tetracosyl amine (CnHaNHz) Pentacosyl amine (CssHmNI-Is) Hexacosyl amine(CssHsaNHz) Heptacosyl amine (Cs'tHssNHs) Octacosyl amine (CssHs'INHs)Nonacosyl amine (CssHssNHz) or the third,-or any other subsequent carbonatoms in the chain.

Examples of such isomeric forms are as follows: Considering the normalstraight chain primary amine, as set forth in the immediately precedingtable, said amine being as for example undecyl amine having the formula(CH3(CH2)10NH:), the isomeric amine thereof is methyl, nonyl, methylamine (CH3(CIII)BCHNH2CH3).

Other isomers of this same normal amine are:

Ethyloctylmethylamine,

CH3 CH2) qcrnmzcmcm Propylheptylmethylamine,

CH3 (CH2) eC'HNH2(CH2) 20H:

Butylhexylmethylamine,

CHnC'I-h) sCHNI-mCHznCI-l'a Diamyl methyl amine,

CH3 (CH2) 4CHNH2(CH2) 40H:

Similar isomeric amines may be prepared from other normal straight chainamines.

Secondary amines which are suitable for carrying out the presentinvention are:

Secondary heptylamine, C'rH15HNC7I-Ii5 Secondary octyl amine,CaHnNHCaI-In Tertiary amines suitable for carrying out the presentinvention are:

Tertiary octylamine, (CaHnhN Tertiary heptyl-amine, (C1H15)3N Secondaryand tertiary amines typified by the above mentioned amines have a numberof isomeric forms which may be used in carrying out the presentinvention. Unbalanced straight chains or split chains result in manyisomers for each amine having all alkyl groups the same.

Irrespective of to which carbon atom the amine group is attached, thematerial is a straight chain primary amine. Not only is it possible touse straight chain and split chain secondary and tertiary amines, butthe isomeric forms of such amines may be used, and these compounds maydiffer from each other only in having an alkyl group substituted for oneor both of the hydrogens in the amine group. If one hydrogen issubstituted for, it would of course, be a secondary amine, and if bothof the hydrogens are substituted for, it would be a tertiary amine.Substituting alkyl groups for hydrogens in the amine group, would tendto result in products of lower water solubility. However, the point ishere made that the amine, irrespective of the substitution that has beenmade, should be one that has negligible water solubility. Further, theamines herein disclosed should preferably have a specific gravity lessthan water, so as to eliminate any tendency of the anti-foam agents tosettle to the bottom of the treatment vessel.

Very satisfactory results have been obtained when the present inventionhas been applied to waters containing sodium or potassium alkalinity,that is, water in which the sodium or potassium alkalies, or theirequivalents, and particularly sodium or potassium hydroxides, carbonatesor bicarbonates, exist in excess of that capable of combining with orexisting in combination with calcium and/or magnesium ions present inthe water.

Alkalinity of this type can exist naturally in the water or may bederived from zeolite treat ment of the water, or may be derived in otherways.

The present invention may be applied to raw waters either hard or softand beneficial results obtained. Water, which has been softened by thelime-soda-ash process or by phosphates, sodium silicates, or otheralkaline treatment, may be treated with an anti-foam composition of thecharacter herein set forth.

It is well known that many substances have decided anti-roam propertieswhen used in conjunction with normal types of water which are free fromexcess alkalinity, such as sodium alkalinity, or which have a lowpercentage of sodium alkalinity. Castor oil and sperm oil typify suchsubstances.

When materials of ths type are added to waters of excess alkalinity, andespecially excess sodium and/or potassium alkalinity, poor or mediocreresults are obtained in reducing the foaming tendency of the water. Itseems probable that the foaming occurring in boiler water is the resultof the concentration of soluble salts and insoluble solids in a state ofsuspension. In waters of excess alkalinity there may be present sodiumand/or potassium bi-carbonates and/or carbonates, and there may bepresent sodium and/or potassium carbonates and/or hydroxides. Underconditions prevailing in an operating boiler, a large percentage of thebi-carbonates and carbonates originally present in the water areconverted into hydroxides. It may well be that because of the presenceof these hydroxides that the usual anti-foam materials are ineffectivewhen added to boiler waters having high or moderately highconcentrations of alkali hydroxides or other alkali materials.

When oils of the above type are added to boiler water, there is atendency for them to be saponifled or react chemically with the alkalihydroxides or other alkali compounds, with the resultant formation ofsoluble sodium and/or potassium soaps. The foaming tendencies of sodiumand potassium soaps are well recognized and the formation of such soapsaccelerate the tendencies of the boiler water to foam.

The following is a specific example, illustrating such acceleration andfoaming tendency. An experimental boiler operating at a pressure of 200lbs. per square inch, with an excess caustic alkalinity in theneighborhood of 200 grains per gallon, was treated with a standardanti-foam material containing 16% of castor oil by weight, theproportion being one-quarter pound of the castor oil material per 1000gallons of water. Immediately after the introduction of the anti-foammaterial, a test showed no foaming occurring. One hour after theintroduction of the anti-foam material, the amount of foaming occurringwas approximately 25% greater than that taking place before theanti-foam material was added. The increase in foaming occurring one hourafter the introduction of the anti-foam material, namely, castor oil, isdue to the saponiiication of the same by the alkalies present in theboiler water.

Steam distillation of the usual anti-foam materials may, in somemeasure, reduce the effectiveness of these anti-foam materials in boilerwater of high or excess sodium or equivalent alkalinity. However, sincemost of the usual anti-foam materials can be used effectively in watercontaining little or no sodium alkalinity, and their effectivenessmaintained, to a large degree at least, for several hours, steamdistillation of the anti-foam material is probably of minor importance.

' no soap of any kind.

In one form of the present invention, water containing alkalinity, andparticularly sodium or potassium alkalinity, is treated with a materialthat is unsaponifiable and does not steam distill to any marked degree.Waters softened by base exchange processes, and especially those whichhave been treated with zeolites or waters having a high natural sodiumcarbonate or sodium bicarbonate alkalinity are typical of waters havingfoaming properties and which may be treated in accordance with thepresent invention, which resides not only in said method, but also inthe utilization of a particular class of anti-foam materials, and themethod of preparing the same. While the average operating boilerpressure is around 200 pounds per square inch, it is to be understoodthat the present invention is applicable to boiler pressures materiallyhigher or lower than 200 pounds per square inch.

The amines of the present invention may be mixed with a dispersingagent, and in the narrower form of the invention, the preferreddispersing agent is tannin, as will be hereinafter more fully pointedout.

It may be stated that three principal typical classes of dispersingagents are available. The first class comprises inorganic colloidalmaterial, such as clays or bentonite; the second class, organic materialwhich contain appreciable quantitles of soap in one form or another; andthe third class, organic materials which are characterized by colloidalproperties and which contain This third class of materials includes theextracts of various woods and barks which would normally be referred toas tannin extracts; extracts of various aquatic plants, such as seaweedsor kelp; and extracts of certain plants and shrubs, such as cactusplants.

Clays or bentonite may, of course, be used, but the disadvantages ofthis type of material makes it inadvisable to use it as the soledispersion agent, since it does not lend itself to the very greatdispersion that is necessary when a very small quantity of ananti-foaming compound is dissolved in a relatively large amount ofboiler feed water. However, the clays or bentonite may be used as thedispersion agent when mixed with other materials, as hereinafter setforth.

The soap dispersion agents may under some circumstances be used, butcertainly not where there is an excess of alkali present, because thesoap, in this case, remaining water soluble would tend to counteract theanti-foam properties of the anti-foam agent, and, moreover, in somecases, function to increase the foaming properties of the boiler waterinstead of decreasing them.

Investigation has shown that tannin is a very desirable dispersingagent, because at least when waters having alkaline constituents aretreated, and particularly boiler waters, the tannin has betterdispersing properties than the clays or soap, while at the same time itdoes not have the disadvantages of the latter classes of materials.

It may be pointed out that tannin in certain cases and in certain typesof waters. has fairly good anti-foam properties and, therefore, the useof tannin in conjunction with a more active antifoam agent results in acomposition having antifoam properties superior to that of either thematerials used separately. Further, the tannin acts as an activedispersing agent for the more active or primary anti-foam material, andthis is highly desirable in a good anti-foam composition. Again, thetannin performs the function of conferring upon the resultingcomposition non-corrosive properties. This is due to the tendency of thetannin extract and similar materials to absorb dissolved oxygen from theboiler feed water or from any other water containing oxygen, whichoxygen, if not removed, is one of the principal causes of boilercorrosion. Tannin, of course, is an example of a material which is anactive dispersing medium and also acts as a cor rosion inhibitor toprevent corrosion of the boiler metal. It is within the province of thepresent invention in its broad form to use other equivalent materialswhich perform the same functions as the tannin performs.

The composition may have present a viscosityincreasing agent or bodyingmaterial. A number of compounds may be used as the bodying agent, but itis preferable to. use corn meal or a material containing starch. Thecorn-meal or starch acts not only as a bodying material, but also as anadditional dispersing agent and increases the dispersion characteristicsof the composition. In accordance with one form of the presentinvention, the anti-foam composition has present a primary dispersionagent, and a secondary dispersion agent, the secondary dispersion agentpreferably acting also as a bodying agent or to increase the viscosityof the anti-foam composition, which, of course, contains anti-foamagents, as hereinbefore pointed out.

The increase in the viscosity of the anti-foam composition is desirablesince this prevents separation of the active anti-foam constituents fromthe remainder of the composition.

The following are examples of methods which may be used to obtain thebodying effect.

In one method the meal or starch is heated in the presence of addedWater or that contained in the liquid tannin extract to a temperaturehigh enough to produce a hydrolysis of the meal. This hydrolyzed mealupon cooling takes on the form of starch paste and acts to increase theviscosity of the anti-foam composition in proportion to the amount ofstarch or meal used. The amount of bodying agent used in the anti-foamcomposition may, of course, vary.

In carrying out the present invention, the primary, secondary ortertiary anti-foam agent may be a simple amine saturated or unsaturated,or a mixed amine, saturated or unsaturated. Further, the primaryanti-foam agent may be a mixture of simple amines saturated orunsaturated, or a mixture of mixed amines, saturated or unsaturated. Theamine compound or the free amine may be formed in situ by decompositionof a suitable salt, said salt upon being added to the water, convertingat least a part of the free salt to the free amine.

The compounds which are useful in carrying out the present invention aregenerally represented by the following formula:

the secondary amine is represented by RRNH, and contains an imino group;and when three hydrogen are replaced, the tertiary amine is formedhaving the formula: RR'R"N.

Since it is desired that the amines be insoluble in the water treatedand do not steam distill to any substantial extent, when boiler water isbeing treated, it is desirable and in fact practically necessary, thatthe amines have a high molecular weight of the character herein setforth. The amines having a relatively low molecular weight are solublein the boiler water, or other water, steam distill to an appreciableextent. It is recognized that the branching of the chain in the chainamines lowers the boiling points of even the high molecular weight aminecompounds having at least eleven carbon atoms in the basic R, R or R"group. However, if the boiling point is not greatly reduced, thesebranch chain compounds may be used in the treatment of boiler water. Forthe above reasons, in the preferred form of the invention, the compoundscoming within the scope of the present invention, should have at leasteleven carbon atoms in the basic alkyl group and preferably in eachalkyl group of the secondary and tertiary amines.

The following is an illustrative example of how the present inventionmay be carried out, there being utilized, in addition to the amineanti-- foam agent, a dispersing agent and/or a bodying agent. While itmay not be necessary in some instances to use a dispersing and/orbodying agent, as a general rule, it is desirable.

The above indicates what is meant by the term "amine having a highmolecular weight." By this term it is intended to cover amines of thecharacter set forth having eleven (11) or more carbon atoms. The higheramines of the series (CnH-2n+1)xNH where y=0, 1 or 2) which have givenvery satisfactory results are heptacedyl amine, stearyl amine, secondarystearyl amine and tertiary stearyl amine. Polysubstituted amines andparticularly those having eleven (11) or more carbon atoms present ineach alkyl group may also be used. The amine, such as heptadecyl amineor stearyl amine may be mixed with a small percentage of corn meal and apredominating quantity of a liquid tannin extract well known in theprior art, and the mixture is heated to a temperature sufficient toproduce a hydrolysis of the meal and to gelatinize the final product.Satisfactory results have been obtained by heating the mixture to about180 F. Higher temperatures may be used. This mixture is fed into theboiler in the form of a water suspension.

As indicated, the preferred form of the antifoam composition forintroduction into the boiler feed water is that of a gelatinizedproduct. Such a gelatinized composition may be made by mixing togetheran amine, such as heptadecyl amine, stearyl amine, or any other amine oramine mixture herein set forth with corn meal and tannin extract.

The ingredients may be mixed in suitable proportions, of which thefollowing Tables I to IV are illustrative:

Table I (1) Corn meal 2%, tannin extract 94%,

amine-4% (2) Corn meal 4%, tannin extract 88%,

amine-8% (3) Corn meal 6%, tannin extract 78%,

amine-16% (4) Corn meal 8%, tannin extract 67%,

amine-25% (5) Corn meal 8%, tannin extract 57%,

amine-35% In general, the amine content 01' the mixture may vary betweenabout 1% to 2% to-35%.

The above percentages are merely illustrative as to the amount of tanninextract and aliphatic amine, and may vary beyond limit of the maximumand minimum above set forth and still come within the spirit of thepresent invention. As hereinbefore pointed out, the primary antifoambase, such as the aliphatic amine, may be used by itself, but it isdesirable that the primary anti-foam agent be used in conjunction withthe tannin, as the tannin assists in the dispersion, and further is initself an anti-foam agent. It is preferred to form a gelatinized productof the ingredients, but here again, it is within the spirit of thepresent invention to use the primary anti-foam agent in an anti-foamcomposition which is not reduced to paste form.

Instead of using corn meal or starch as the viscosity-increasing orbodying agent, various other such agents may be used, as for example,dextrine. When using dextrine, satisfactory results have been obtainedwhen the mixture contained from 5% to 50% of dextrine, which is adegradation product of starch. Instead of using corn meal, starch ordextrine, other bodying agents may be used. Gums, such as gumtragacanth, gum acacia and locust bean gum, which are additionalexamples of suitable bodying agents, give good results.

The following examples illustrate how the dispersion agents and thebodying agents may be varied:

Table II Amine Tannin extract Corn meal Percent Percent Percent TableIII Tannin Benton- Corn Amine extract its starch Percent Percent PercentPercent 2 87 5. 0 6. O 6 84 5. 0 6. 0 10 79 5.0 6.0 15 74 5. 0 B. D 2070 5.0 6.0 30 61 5.0 6. O 35 56 5.0 6.0

Table IV Amine Tannin extract British gum Percent Percent Percent 2 8612 5 83 l2 10 78 12 15 73 12 20 88 12 30 58 12 36 53 i2 It is desired topoint out that the above examples are merely illustrative of suitablecombinations of dispersing agents and bodying agents with the amines,and that various other dispersing agents and bodying agents may be usedand still come within the spirit of the present invention.

While usually the amount of bodying agent will vary from 2% to 8%, itmay be much higher, as for example, when using dextrine, up to about 50%by weight of the mixture may be dextrine, and again it is not necessarywith some of the body agents that the lower limit be 2%. Less than 2%may be used, and while 2% may be considered a satisfactory lower limitfor starch, if the starch is used in conjuction with other thickeningagents, such as a gum, then the starch may be reduced to less than 2%.

A paste mixture prepared as set forth and containing a primary anti-foamagent, a secondary anti-foaming agent, which preferably has dispersingproperties, and a bodying agent of the character herein set forth may beadded to boiler water to prevent foaming thereof. More specifically, anyof the compositions herein set forth may be added to the boiler water inthe ratio of one-quarter pound of the composition per 1000 gallons ofwater. The amount which may be added is strictly illustrative, and isnot to be taken by way of limitation. Obviously, the amount of anti-foammaterial which is added to the water will depend upon thecharacteristics of the water. For example, in another experiment it wasfound that as low as one-twentieth & of a pound of the anti-foamcomposition per 1000 gallons of water was satisfactory. In still anothercase two (2) pounds of the antifoam composition per 1000 gallons ofwater positively inhibited the anti-foam tendency of the boiler feed. Inthe last named example, where the amine constitutes 35% by weight of theantijoam material, the concentration of the amine is about 84 parts permillion parts of water treated. Larger arounts of the amine than thoseindicated can also be employed where necessary, although a practicallimit of 500 parts per million will be indicated, primarily for reasonsof economy.

The above mixtures and similar mixtures were added to water of thecharacter that the castor oil, previously referred to, was added, andthe conditions of the tests were the same.

Tests taken immediately after the introduction of the anti-foamcomposition showed no foaming occurring. Tests made two and one-half (2hours after the introduction of the anti-foam material showed thefoaming to be practically nil. Tests which were made after continuousheating of the anti-foam material in the boiler water, under the aboveconditions, for eight (8) hours, showed a tendency to foam, which wasonly a small fraction of the foaming occurring before the anti-foam wasadded. After twenty hours the tendency to foam was not quite as great asthat exhibited by the untreated water. Even in the presence of theanti-foam material, there is some tendency to foam. and the amount offoaming in the presence of the antifoam material. may vary from a verysmall percentage to to of the foaming that occurs before the anti-foammaterial is added.

The compounds herein set forth give markedly superior results whentreating water containing excess alkalinity. If castor oil, which is awell known anti-foaming agent for water which does not contain excessalkalinity, were used, the oil would become saponiiled and therebyrendered ineifective and/or harmful. In raw water and water softened inany well known manner, as for example by the lime-soda-ash process, theamines as hereinbefore described are also effective.

The herein referred to amines and amine compounds can each be mixed withthe other to form the active anti-foam agent. Moreover, the mixture maycontain more than two amines or amine compounds. The primary amines mayhave an additional primary amine of the character herein set forth, or aplurality of amines mixed therewith to form the amine anti-foam agent.The secondary amines may be mixed with a single amine or a plurality ofother secondary amines, and the tertiary amines may be mixed with asingle other tertiary amine, or a plurality of tertiary amines to formthe active anti-foam agent. Moreover, any of the primary amines hereinreferred to may be mixed with any of the secondary amines or theanti-foam agent may comprise a mixture of a primary amine compound, asecondary amine compound, and a tertiary amine compound,-or a mixturethereof. The tertiary amines may also be mixed with each other to formthe active anti-foam compound. It is not thought necessary to refer toall of the mixtures of primary amine compounds and/or secondary aminecompounds and/or tertiary amine compounds which may be used in carryingout the present invention. However, as a. specific example, it may bestated that secondary stearyl amine and tertiary stearyl amine may bemixed together with the tannic compounds herein referred to and abodying agent, and excellent results be obtained. The presentapplication is a continuation-inpart of applications Serial Nos.193,366, 193,367 and 193,368, all filed March 1, 1938, each of saidapplications being a continuation in-part of application Serial N0. 579,filed January 5, 1935.

While starches, starch degradation products, and gums may be used asbodying agents, broadly any bodying agent may be used which willfunction to increase the viscosity of the mixture. The bodying agent maybe a mixture of organic bodying agents or a mixture of inorganic agents,or the bodying agent may be a mixture of organic and inorganiccompounds. As herelnbefore stated, it is preferred that the secondarydispersing agent, such as bentonite. and the like, act as a bodyingagent.

The expression comprising introducing into the bath a compositioncontaining as its essential anti-foam agent an aliphatic amine," orequivalent expressions, as used in some of the claims, is intended tocover the introduction of the amine into the bath or of the bath intothe amine.

I claim as my invention:

[1. The process of treating water which includes adding to the water asmall amount, not to exceed five hundred parts per million, of acompound chosen from the group consisting of aliphatic primary andsecondary amines having at least six carbon atoms in an alkyl groupthereof.]

[2. The method of treating water containing solids in the state ofsuspension to prevent said solids from deleteriously affecting thewater, comprising adding to the water an aliphatic amine in an amountnot exceeding 500 parts per million, said amine having at least sixcarbon atoms in an alkyl group thereof] 3. The method of conditioning anaqueous bath having ingredients present inducing foaming thereincomprising introducing into the bath a composition containing as itsessential anti-foam agent an aliphatic amine containing at least elevencarbon atoms in an alkyl radical thereof, said amine being characterizedby the properties of being insoluble in the bath, and showing littletendency to saponify with the ingredients of the bath, the anti-foamagent being present in an amount suflicient to inhibit foaming of thebath.

4. The method of conditioning an aqueous bath containing excessalkalinity and having ingredients present inducing foaming thereincomprising introducing into the bath containing excess alkalinity acomposition containing as its essential anti-foam agent an aliphaticamine containing at least eleven carbon atoms in an alkyl radicalthereof, said compound being characterized by the properties of beinginsoluble in the bath and showing little tendency to saponify with theingredients of the bath, the anti-foam agent being present in an amountsufficient to inhibit foaming of the bath.

5. Boiler water containing alkaline constituents and carrying analiphatic amine compound foam inhibitor containing at least elevencarbon atoms in an alkyl radical thereof, said inhibitor being presentin an amount which inhibits foaming of the boiler water and beingcharacterized by the properties of being substantially insoluble in theboiler water, steam distilling to a negligible extent and showing littletendency to saponify.

6. Boiler water containing alkalineconstituents and carrying analiphatic amine compound foam inhibitor containing at least elevencarbon atoms in an alkyl radical thereof and having the general formula(CnHZn+I)XNHy, where x is an integer and y is selected from the groupconsisting of 0, 1 and 2, said inhibitor being characterized by theproperties of being substantially insoluble in the boiler water, steamdistilling to a negligible extent and showing little tendency tosaponify.

7. The method of conditioning an aqueous bath having an alkaliconstituent comprising introducing into said aqueous bath having analkali constituent a composition containing as its essential anti-foamagent an aliphatic amine containing at least eleven carbon atoms in analkyl radical thereof and characterized by the properties of beingsubstantially insoluble in the aqueous bath being treated, steamdistilling to a negligible extent, and showing little tendency tosaponify with the ingredients of the bath, said amine being present inan amount sufficient to inhibit foaming of the aqueous bath.

8. The method of conditioning boiler water having present ingredientsinducing foaming therein, comprising introducing into the boiler water acomposition containing as its essential anti-foam agent an aliphaticamine characterized by the properties of being substantially insolublein the boiler water being treated, steam distilling to a negligibleextent and showing little tendency to saponify with the ingredients ofthe bath, the amine being present in an amount sufficient to inhibitfoaming of the bath, said amine compound being represented by thefollowing formula:

in which R is an alkyl group containing at least eleven carbon atoms;and R and R are selected from the group consisting of hydrogen and analkvl group.

9. The method of conditioning boiler water comprising introducing intosaid boiler water a composition containing a dispersing agent, and asits essential anti-foam agent an aliphatic amine containing at leasteleven carbon atoms in an alkyl radical thereof and characterized by theproperties of being substantially insoluble in the boiler water beingtreated, steam distilling to a negligible extent, and showing littletendency to saponify with the ingredients of the boiler water, saidamine being present in an amount sufiicient to inhibit foaming of theboiler water.

10. The method of conditioning boiler water comprising introducing intosaid boiler water a composition containing a tannin dispersing agent,and as its essential anti-foam agent an aliphatic amine containing atleast eleven carbon atoms and characterized by the properties of beingsubstantially insoluble in the boiler water being treated, steamdistilling to a negligible extent, and showing little tendency tosaponify with the ingredients of the boiler water, said amine beingpresent in an amount sufficient to inhibit foaming of the boiler water.

11. The method of conditioning boiler water comprising introducing intosaid boiler water a composition containing as its essential antifoamagent an aliphatic amine containing at least eleven carbon atoms, adispersing agent for said amine and a bodying agent for increasing theviscosity of the composition, said amine being present in an amountsufficient to inhibit foaming of the boiler water and characterized bythe properties of being substantially insoluble in the boiler waterbeing treated, steam distilling to a negligible extent, and showinglittle. tendency to saponify with the ingredients of the boiler water.

12. The method of conditioning boiler water comprising introducing intosaid boiler water a composition containing as its essential anti-foamagent an aliphatic amine containing at least eleven carbon atoms, atannin dispersing agent for said amine and a bodying agent forincreasing the viscosity of the composition, said amine being present inan amount suillcient to inhibit foaming of the boiler water andcharacterized by the properties of being substantially insoluble in theboiler water being treated, steam distilling to a negligible extent, andshowing little tendency to saponify with the ingredients of the boilerwater.

13. The method of conditioning boiler water comprising introducing intosaid boiler water a composition containing as its essential anti-foamagent an aliphatic amine containing at least eleven carbon atoms, atannin dispersing agent for said amine and a carbohydrate bodying agentfor increasing the viscosity of the composition. said amine beingpresent in an amount suiilcient to inhibit foaming of the boiler waterand characterized by the properties of being substantially insoluble inthe boiler water being treated, steam distilling to a negligible extent,and showing little tendency to saponify with the ingredients of theboiler water.

14. The method of conditioning boiler water comprising introducing intosaid boiler water a composition containing s its essential anti-foamagent an aliphatic amine containing at least eleven carbon atoms, adispersing agent for said amine and a carbohydrate bodying agent forincreasing the viscosity of the composition, said amine being present inan amount sufficient to inhibit foaming of the boiler water andcharacterized by the properties of being substantially insoluble in theboiler water being treated, steam distilling to a negligible extent, andshowing little tendency to saponify with the ingredients of the boilerwater.

15. The method of conditioning boiler water which has been softened bythe lime-soda process comprising introducing into said water which hasbeen softened by the lime soda process a composition containing as itsessential anti-foam agent an aliphatic amine containing at least elevencarbon atoms in an alkyl radical thereof and characterized by theproperties of being substantially insoluble in the boiler water beingtreated, steam distilling to a negligible extent, and showing littletendency to saponify with the ingredients of the boiler Water, saidamine being present in an amount sufficient to inhibit foaming of theboiler water.

16. The method of conditioning boiler water which has been softened bytreatment with a zeolite comprising introducing into said water whichhas been softened by treatment with zeolite, a composition containing asits essential anti-foam agent an aliphatic amine containing at leasteleven carbon atoms in an alkyl radical thereof and characterized by theproperties of being substantially insoluble in the boiler water beingtreated, steam distilling to a negligible extent, and showing littletendency to saponify with the ingredients of the boiler water, saidamine being present in an amount suflicient to inhibit foaming of theboiler water.

1'7. An anti-foam composition for treating boiler Water to inhibitfoaming therein, said composition comprising as its essential anti-foamagent an aliphatic amine compound containing at least eleven carbonatoms, a tannin as a dispersing agent, and a bodying agent whichincreases the viscosity of the composition and which inhibits theseparation of the anti-foam constituents from the composition, saidamine compound being characterized by the properties of beingsubstantially insoluble in the boiler water being treated, steamdistilling to a negligible extent, and showing little tendency tosaponify with the ingredients of the boiler water, said amine compoundbeing present in an amount which does inhibit foaming.

18. An anti-foam composition for treating boiler water to inhibitfoaming therein, said composition comprising as its essential anti-foamagent an aliphatic amine compound containing at least eleven carbonatoms, a tannin as a dispersing agent, and a carbohydrate bodying agentto increase the viscosity of the composition, said amine compound beingcharacterized by the properties of being substantially insoluble in theboiler water being treated, steam distilling to a negligible extent, andshowing little tendency to saponify with the ingredients of the boilerwater.

19. The method of conditioning an aqueous bath having presentingredients inducing foaming therein, comprising introducing into thebath a composition containing as its essential antifoam agent a mixtureof primary, secondary and tertiary aliphatic amines, each of said aminescontaining at least eleven carbon atoms in an alkyl radical thereof,said mixture of amines being characterized by the properties of beinginsoluble in the bath, and showing little tendency to saponify with theingredients of the bath, the anti-foam agent being present in an amountwhich does inhibit foaming of the bath.

20. The method of conditioning boiler water 14 having present alkalineingredients inducing foaming therein, comprising introducing into theboiler water a composition containing as its essential anti-foam agent amixture of primary, secondary, and tertiary aliphatic amines, each ofsaid amines containing at least eleven carbon atoms in an alkyl radicalthereof, said mixture of amines being characterized by the properties ofbeing insoluble in the boiler water, and showing little tendency tosaponify with the ingredients of the boiler water, the anti-foam agentbeing present in an amount which does inhibit foaming of the boilerwater.

21. The method of conditioning an aqueous bath having presentingredients inducing foaming therein, comprising introducing into thebath a composition containing as its essential antifoam agent a mixtureof secondary and tertiary aliphatic amines, each of said aminescontaining at least eleven carbon atoms in an alkyl radical thereof,said mixture of amines being characterized by the properties of beinginsoluble in the bath, and showing little tendency to saponify with theingredients of the bath, the anti-foam agent being present in an amountwhich does inhibit foaming of the bath.

22. The method of conditioning boiler water having present alkalineingredients inducing foaming therein, comprising introducing into theboiler water a composition containing as its essential anti-foam agent amixture of secondary and tertiary aliphatic amines, each of said aminescontaining at least eleven carbon atoms in an alkyl radical thereof,said mixture of amines being characterized by the properties of beinginsoluble in the boiler water, and showing little tendency to saponifywith the ingredients of the boiler water, the anti-foam agent beingpresent in an amount which does inhibit foaming of the boiler water.

23. The method of conditioning an aqueous bath having presentingredients inducing foaming therein, comprising introducing into thebath a composition containing as its essential anti-foam agent analiphatic amine characterized by the properties of being substantiallyinsoluble in the aqueous bath being treated, steam distilling to anegligible extent and showing little tendency to saponify with theingredients of the bath, the amine compound being present in an amountsuflicient to inhibit foaming of the bath, said amine compound beingrepresented by the following formula:

R! in which R is an alkyl group containing at least eleven carbon atoms;and R and R" are selected from the group consisting of hydrogen and analkyl group.

24. The method of conditioning an aqueous bath having ingredientspresent inducing foaming therein comprising introducing into the bathstearyl amine.

25. The method of conditioning an aqueous bath having ingredientspresent inducing foaming therein comprising introducing into the bath amixture of stearyl amine, tannin, and a carbohydrate which increases theviscosity of the mixture, said stearyl amine being present in an amountsuflicient to inhibit foaming of the bath.

26. The method of conditioning boiler Water having present ingredientsinducing foaming comprising introducing into the boiler water aheptadecyl amine.

27. Boiler water containing alkaline constituents and carrying as aninhibitor of foaming heptadecyl amine.

28. The process of treating water which includes adding to the water inan amount not in excess of 500 parts per million, a compound selectedfrom the group consisting of aliphatic primary and secondary amines andsalts of such amines readily hydrolyzable into the free amines, saidamines having at least eleven carbon atoms in an alkyl radical thereofper molecule.

29. The method of treating water containing solids in the state ofsuspension to prevent said solids from deleteriously afiecting thewater, comprising adding to the water an aliphatic amine in an amountnot exceeding 500 parts per million, said amine having a total of atleast eleven carbon atoms in an alkyl radical thereof per molecule.

30. The method of treatin boiler water having a tendency to foam onboiling which comprises dispersing into said water in an amount not inexcess of 500 parts per million, an amine selected from the groupconsisting of aliphatic primary amines, aliphatic secondary amines, and

16 mixtures of said primary amines and secondary amines, said aminecontaining at least eleven carbon atoms in an alkyl radical thereof permolecule, and boiling the resulting dispersion.

31. A method as claimed in claim 28 wherein the alkyl radical is anocta'decyl radical.

WAYNE L. DENMAN.

REFERENCES CITED The following references are of record in the file ofthis patent or the original patent:

UNITED STATES PATENTS OTHER REFERENCES Sharples Synthetic OrganicChemicals, 1937, 10th ed., page 28.

